I just went through the whole conversation between my characters and the barbarian chief - ends up that I have to fight a few. That is where I am stuck - does anyone have any suggestions for this battle?

Well, without knowing specifis of your party composition and average level, just the usual: hold person, confusion, cloudkill, death fog, web, chromatic orb, etc. If any of them are clerics then target them with Melf's acid arrow to stop their spells.

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